Premotor cortex hemodynamics reflect internal auditory category, not reported category

In sensory decision-making tasks, animals’ decisions are driven by perception, but also by non-perceptual factors. Because of external and internal noise, stimuli may be internally misclassified, leading to perceptual errors. But other, non-sensory factors such as impulsivity or exploratory behavior can lead to non-perceptual errors. Here we exploited the neural traces of these errors in frontal cortex to provide insights into their role in sensory decision making. Using functional ultrasound imaging (fUS), we investigated how the premotor cortex (PMC) in ferrets represents stimuli in a categorization task, varying the difficulty in order to manipulate the rates of perceptual errors. We found that PMC activity reflects the objective (and not the chosen) stimulus category on incorrect Easy trials, when non-perceptual errors are more likely. In contrast, PMC responses correlate with the chosen category (and not objective category) on incorrect Difficult trials, when perceptual errors are more likely. These results suggest that PMC encodes the ferret’s perceptual decision but not necessarily the final motor decision. Perceptual errors could be refined further by assessing licking patterns, but licking patterns alone did not explain the effect. This study advances our understanding of the functional role of the frontal cortex in decision making, suggesting that the PMC integrates sensory inputs to guide behavior based on perceptual, rather than motivational, information.